Upgrade to Rails 7.1 and apply new framework defaults

* Remove deprecated options from environments
* Remove deprecation warnings for upcoming Rails 7.2
* Dump schema with new defaults
* Remove outdated (and erroneous) data attribute in view
* Resolve a `NoMethodError` for seeds_spec.rb

Gemfile

@@ -35,7 +35,9 @@ gem 'proformaxml', '1.0.0'
 gem 'prometheus_exporter'
 gem 'puma'
 gem 'pundit'
-gem 'rails', '~> 7.0.8'
+# TODO: Temporary switch to Rails 7.1 branch until the next release.
+# See https://github.com/rails/rails/pull/49778
+gem 'rails', github: 'rails/rails', branch: '7-1-stable'
 gem 'rails_admin', '< 4.0.0'
 gem 'rails-i18n'
 gem 'rails-timeago'